Sheet control system for paper cutters



y 1965 w. J. HASELOW ETAL 3,

SHEET CONTROL SYSTEM FOR PAPER CUTTERS Filed Jan. 21, 1963 INVENTORS:

United States Patent '0 Sunni" CONTROL srsrnM FOR PAPER omens William J.Haseiow and Wiliiain E. Aschenbrenner,

Wisconsin Rapids, Wis., assignors to Consolidated Papers, -Inc.,Wisconsin Rapids, Wis., a corporation of Wisconsin Filed Jan. 21, 1963,Ser. No. 252,950 7 .-Claims. (Cl. 83-24) The present invention relates.to apparatus for cutting continuous webs of paper into sheets, and moreparticclarly, to an apparatusfor controlling the movement of a sheet ofpaperonce-it is severed from the web.

Heretofore, sheets of paper cut from a continuous paper web by means ofa rotary cutter had a tendency .to whip with the result that thetrailing edges of the sheets were frequently crumpled due to secondaryimpact by the cutter, corners were often turned and some of the sheetswere folded, thereby creating difficulties in cutter operation andcausing jamming as the-sheets were fed .to the layboy. Particularditliculty has been experienced when using ;an automatic sheet samplerin conjunction with the rotary cutter. To minimize the .difliculties ithas been necessary to limit the cutter operatingspeed.

.A principal object of the invention is to provide apparatus forcontrolling the movement .of sheets of paper and the like immediatelyafter severing from the web so that they will not be damaged and may betransported away from the cutter insuch manner as to be efficiently andeffectively assembled :or stacked.

Another .object ,of "the .invention is to provide appara- :tus forcontrolling the movement of sheets of paper and thelike that have .beensevered from a continuous .web by meansof a rotary cutter bycounteracting the forcesztending to cause the severed sheets to whip. Inparticular,

it is anobjectof the invention to counteract the affect on the severedsheets of the low pressure areas at the-periphery ,of the rotary cutterwhich are created its rotation.

A further object of the invention is the provision of apparatus ,of thecharacter described whichis efiicient and effective in use, which may beadjusted forlefficient use with paper sheets of different widths, andwhich facilitates greatly increased cutter operating speeds.

v,(Zither objects and advantages of the invention will become apparentin the following detailed description.

Now, in order'to acquaint those skilled in the art with themannerofmakingand using our sheet control system, we shall describe, inconnection wit-h the accompanying drawings, the preferred embodiment ofour invention and the preferred manner of making and using the same.

In the drawings:

FIGURE 1 is a diagrammatic view, in side elevation, of a paper cuttingand sheet feeding machine embodying the apparatus of the presentinvention;

FIGURE 2 is a fragmentary perspective view of a combined paper cuttingand feeding machine embodying the sheet control apparatus ,of theinvention;

FIGURE 3 is a fragmentary plan view of sheet control apparatus made inaccordance with the invention; and

FIGURE 4 :is a vertical sectional view taken substantially on line 44 ofFIGURE 3. I

Referring now to the drawings, and particularly to FIGURE 1, thecombined sheet cutting and feeding machine embodying the presentinvention includes a feed roll 12 and a cooperating roll 14 betweenwhich is fed, by rotation of the roll 12 in the direction of the arrow,a web 16 of sheet material such as paper or the like. The web 16 is fedangularly downwardly on a doctor board 18 to be severed by means of acutting assembly 20. The cutting assembly 20 includes a suitably drivenice cutting roll 22 having a radially outwardly extending blade 24 whichcooperates with a bed knife 26 to sever the web l6 into a plurality ofindividual sheets of equal length. .Once severed from the web, thesheets are directed to a transport tape conveyor 28 by means of aninclined guide tape conveyor 30 whose tapes 32 move in the direction ofthe arrow in FIGURE 1 and are disposed between tapes 34 of the tapeconveyor 28, as shown best in FIG- URE 2. Cooperating with the tapeconveyor 30 is a guide tape conveyor 36 having a plurality of tapes 38(only one of which is shown) which cooperate with the tapes 34 of theconveyor 23 in feeding the severed sheets to the right, as viewed inFIGURE 1, after the sheets leave the inclined tapes 32.

Generally, the tape conveyors 28, 30 and 36 are operated at a linealspeed greater than the lineal speed of web feed so as to pull the webtaut to facilitate cutting and then to expedite the cut sheet away fromand out of the path of movement of the cutter 24. Despite the intendedpurpose of the high speed tapes, the sheets due to whipping arefrequently damaged-or folded by the cutter re-striking the trailing edgeof the sheets.

Accordingto thepresent invention, means are provided for eliminatingwhipping and for assuring effective content of the severed sheetswiththe tapes 32 so that the severed sheets are fed rapidly and in flatcondition to the bight of thetapes 38 and without being re-struck by thecutter. To this end, we provide vacuum apparatus .40 including a suctionbox .42 divided by partitions 44 into a plurality of suction chambers46. Each of the suction chambers 46 is connected by conduit means .48 toa vacuum header 5!) which in turn is connected to arsuitable vacuumsource by meansof a pipe52.

A plurality of1valvesr54 control vacuum communication between theseveralchambers 46 and headerfitl. By this arrangement one or more ofthe chambers46 may be cut oif from the vacuum source in the event thatthe width of the severed sheets is less than the-length of the suctionbox 42. Each conduit 48 preferably, includes a :flexible sectionfacilitating assemblyand disassembly of the described components andserving as a vibration dampener between :the suction box andthevacuumheader and supply means. The suction box 42 is illustrated asbeing vsemi-circular in cross-section and is provided with a flat :coverplate :56 having a plurality of openings 58. The box 42 is disposedatright angles to the conveyor tapes with the face or cover plate '56thereof substantially in contact with-the lower surfaces of the upperrun of the tapes 3 2.

It will be appreciated that a low pressure zone is created at theperiphery of the cutter roll 22 because of the cooperating elements 24and '26 of the cutting assembly .29. This low pressure are-a tends toinduce the leading edge of the severed sheets to rise. As a result, thesheets :tend to whip and do not come-to rest on the tapes 32, and thehigh speed tapes therefore fail to accomplish theirintende'd purpose. Byuse of the vacuum apparatus of .the present invention, each severedsheet'is induced to come immediately'into flush engagement with thetapes 32 and thereby to pass into the bight of the tapes 38 and 34 flatcondition without being re-struck by the cutter blade 24. t V

The sheet control apparatus of the present invent-ion exhibitscharacteristics of great advantage in efficient-cutting and feeding ofsevered sheet material. By use of the apparatus whipping of the sheetshas been eliminated, thereby eliminating turned corners and folded sheetdefects. In actual operation, the present invention has produced theresult of increasing cutter operating speeds from an average of 290 feetper minute to 420 feet per minute, and has at the same time mitigatedfolded sheets and jamming of and shut-down time on the cutters. Thus,the objects and advantages of the invention have been shown herein to beattained in a convenient, economical and practical manner.

While we have shown and described what we regard to be the preferredembodiment of our invention, it will be appreciated that variouschanges, rearrangements and modifications may be made the-rein withoutdeparting from the scope of the invention, as defined by the appendedclaims.

We claim:

1. Apparatus for conveying sheets of material away from a rotary cuttercomprising conveyor means arranged to receive sheets from the cutter,means for biasing the said sheets toward said conveyor means, saidbiasing means comprising a suction assembly including an elongatedsuction box mounted beneath said conveyor means transversely of tr cdirection of sheet movement, said box having a plurality of partitionstherein spaced apart transversely of the dir ection'of sheet movementdividing the interior thereof into a plurality of suction chambers,conduit means communicatively connecting each of said chambers to avacuum source, and valve means in each of said conduit means.

2. A combined cutting and handling apparatus for sheet material forcutting a continuous web of sheet material into sheets of predeterminedlength comprising a rotating cutter roll, a cutting assembly including abed knife and a cooperating knife on the periphery of said roll, feedrolls for moving the web to said cutting assembly, a conveyor extendingadjacent and below said cutting assembly for transporting sheets awayfrom said cutting assembly, and means mounted in operative relation tosaid conveyor for preventing the leading edge of each sheet fromwhipping, said means comprising an elongate vacuum box extendingtransversely of and abutted against the under surface of said conveyoradjacent but downtransport conveyor for moving severed sheets away fromthe cutter assembly, said transport conveyor having a plurality ofspaced tapes, a pair of guide tape conveyors for directing the severedsheets to the upper surface of the tapes of said transport conveyor, oneof said guide conveyors being angularly disposed with respect to saidtransport conveyor and having a plurality of spaced tapes interleavedwith the tapes of said transport conveyor, the other of said guideconveyors being operable to urge the leading edge of each severed sheetinto engagement with the tapes of said transport conveyor, saidconveyors being operated at a greater lineal speed than said feed rolls,the improvement comprising means for assuring initial contact of theleading edge of each of the severed sheets with the tapes of said oneguide conveyor, said means comprising a vacuum assembly including .anelongated suction box disposed in abutment with the under surfaces ofthe tapes of said first guide conveyor, said suction box beingcommunicatively connected to :a .vacuum source.

4. In combined cutting and handling apparatus as set forth in claim 3,said suction box being divided into a plurality of individual suctionchambers, a vacuum manifold communicatively connected to a vacuumsource, conduit means connecting each of said chambers to said manifold,and valve means in each of said conduit means for selectivelycontrolling the evacuation .of each of said chambers.

5. Combined web cutting and sheet handling apparatus for cutting acontinuous web of sheet material into individual sheets, comprising arotating cutter roll, a web cutting assembly including a knife on theperiphery of said roll and a co-operating knife, feed rolls for movingthe web to said cutting assembly, conveyor means extending adjacent butbelow said cutting assembly for transporting sheets cut from the webaway from said cutting assembly, and means mounted in operative relationto said conveyor means adjacent but downstream from said cuttingassembly for mitigating whipping of the leading edge of each sheet andfor causing the leading edge and the progressively following portions ofeach sheet to engage said conveyor means.

6. Combined web cutting and sheet handling apparatus for cutting acontinuous web of sheet material in individual sheets, comprising arotating cutter roll, a web cutting assembly including a knife on theperiphery of said roll and a co-operating knife, feedrolls for movingthe web to said cutting assembly, conveyor means extending adjacent butbelow said cutting assembly for transporting sheets cut from the webaway from said cutting assembly, said conveyor means being operated at agreater lineal speed than said feed rolls, and means extendingtransverse-.

ly of said conveyor means in co-operative relation there- 'with adjacentbut downstream from said cutting assembly for creating a pressuredifferential between the opposite sides of each sheet with the greaterpressure acting do-Wnwardly on the upper side of the sheet, said meansbeing positioned to create said pressure differential over the fulllength of each sheet as the sheet passes said means for pressing theleading edge and the progressively following portions of each sheet intoengagement with said conveyor means and thereby mitigating whipping ofthe leading edge.

7. A process of handling a continuously moving web of flexible sheetmaterial and sheets cut therefrom by cutting means operatingintermittently on the continuously moving web to eliminate bent cornersand fold defects in the sheets consequent upon cutting, comprising thesteps of applying to the leading end portions of the web at a pointadjacent but downstream from the cutting means a conveying force ofgreater speed than the speed of web movement, physically pressing theleading end and progressively following portions of the web against theconveying means prior to and during cutting of the web, and

v physically pressing the progressively following portions and thetrailing edge of the sheet cut from the web away from the cutting meansand against said conveying means.

References Cited by the Examiner UNITED STATES PATENTS 7 705,041 7/02Copland 83-100 2,324,950 7/43 Pratt 83-400 2,546,221 3/51 Funk 83-400 X2,615,518 10/52 Hornbostel 83-24 X 2,796,128 6/57 Denck 83-24 2,865,44912/58 Frankenburg 83-100 2,976,751 3/61 Duba 83-2'4 WILLIAM W. DYER,JR., Primary Examiner.

HUNTER C. BOURNE, JR., ANDREW R. JUHASZ, Examiners.

1. APPARATUS FOR CONVEYING SHEETS OF MATERIAL AWAY FROM A ROTARY CUTTERCOMPRISING CONVEYOR MEANS ARRANGED TO RECEIVE SHEETS FROM THE CUTTER,MEANS FOR BIASING THE SAID SHEETS TOWARD SAID CONVEYOR MEANS, SAIDBIASING MEANS COMPRISING SUCTION ASSEMBLY INCLUDING AN ELONGATED SUCTIONBOX MOUNTED BENEATH SAID CONVEYOR MEANS TRANSVERSELY OF THE DIRECTION OFSHEET MOVEMENT, SAID BOX HAVING A PLURALITY OF PARTITIONS THEREIN SPACEDAPART TRANSVERSELY OF THE DIRECTION OF SHEET MOVEMENT DIVIDING THEINTERIOR THEREOF INTO A PLURALITY OF SUCTION CHAMBERS, CONDUIT MEANSCOMMUNICATIVELY CONNECTING EACH OF SAID CHAMBERS TO A VACUUM SOURCE, ANDVALVE MEANS IN EACH OF SAID CONDUIT MEANS.